System for Forming a Movable Slab Foundation

ABSTRACT

An embodiment of the system for forming a movable slab foundation as comprised by the present invention has a slab foundation, at least one support pier, at least one housing, a seal plate, and at least one support sleeve. The seal plate is positioned within the at least one housing and its outer peripheries are sealingly engaged with the inner surfaces of the at least one housing. The at least one housing and the seal plate are positioned within the at least one support pier. The at least one support sleeve is encased within the slab foundation and its lower end is positioned in abutting contact with the housing. A port is located in and extends through the upper end of the housing and into a cavity between the housing and the seal plate. The at least one housing is capable of movement upward relative to the seal plate.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. ProvisionalPatent Application No. 61/238,291, filed on Aug. 31, 2009, and hereinincorporated by reference in its entirety.

FIELD OF THE INVENTION

This invention relates in general to forming an adjustable foundation,and in particular, to a concrete slab foundation capable of being raisedabove the ground.

BACKGROUND OF THE INVENTION

Many structures have been built on foundations or slabs made of concretepoured on top of soil. Constant changes in the weather and moisturelevels in the soil frequently cause damage to such a foundation. In manyinstances, the foundation may buckle or even crack. This phenomenonoccurs for a variety of reasons, including uneven changes in the watercontent of supporting soils, uneven compacting of soils, and unevenloads being placed on soils. Over time, uneven movement in the soilsunder a foundation can cause a foundation to bend or crack.

Therefore, it would be desirable to provide a method and apparatus thatwould allow a foundation to be poured on top of soil and subsequentlyraised to a desired height to eliminate potential problems caused bysoil movement and/or problematic soils.

SUMMARY OF THE INVENTION

An embodiment of the system for forming a movable slab foundation ascomprised by the present invention has a slab foundation and at leastone support pier. At least one housing is positioned within the at leastone support pier. The at least one housing has a closed upper end and anopen lower end. A seal plate is positioned within and surrounded by theat least one housing. The outer peripheries of the seal plate sealinglyengage the inner surfaces of the at least one housing. The at least onehousing is upwardly moveable within the support pier relative to theseal plate. A cavity is defined by the space between the upper surfaceof the seal plate and the upper end of the at least one housing. A portis located in and extends through the closed upper end of the at leastone housing and into the cavity. At least one support sleeve is encasedwithin the slab foundation. The bottom surface of the at least onesupport sleeve abuttingly contacts the upper end of the at least onehousing.

An embodiment of the system for forming a movable slab foundation ascomprised by the present invention has a slab foundation and at leastone support pier. At least one housing is positioned within the at leastone support pier. The at least one housing has a closed upper end and anopen lower end. A seal plate is positioned within and surrounded by theat least one housing. The outer peripheries of the seal plate sealinglyengage the inner surfaces of the at least one housing. The at least onehousing is upwardly moveable within the support pier relative to theseal plate. A cavity is defined by the space between the upper surfaceof the seal plate and the upper end of the at least one housing. A portis located in and extends through the closed upper end of the at leastone housing and into the cavity. At least one support sleeve is encasedwithin the slab foundation. The bottom surface of the at least onesupport sleeve abuttingly contacts the closed upper end of the at leastone housing. A pumping device is connected to the port for pumping asupport media into the cavity to thereby expand the cavity and move thehousing, the support sleeve, and the slab foundation upwards relative tothe seal plate.

An embodiment of the present invention is directed to a method forforming a movable slab foundation. The method comprises providing ahousing with a closed upper end and an open lower end. A seal plate ispositioned within and surrounded by the housing. The outer peripheriesof the seal plate are sealingly engaged with the inner surfaces of thehousing. A cavity is defined by the space between the upper end of thehousing and the upper surface of the seal plate. A port located in andextends through the closed upper end of the housing and into the cavity.A support pier is placed below an intended slab foundation area. Theinner and outer surfaces of the housing are treated with a formreleaser. The housing and the seal plate are positioned within thesupport pier. A support sleeve is placed in abutting contact with theclosed upper end of the housing. A slab foundation is formed such thatit encases the support sleeve. A support media is pumped through theport and into the cavity, thereby expanding the cavity andsimultaneously lifting the housing and the support sleeve to move theslab foundation upward relative to the seal plate to a desired height.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the features and benefits of the invention,as well as others which will become apparent, may be understood in moredetail, a more particular description of the invention brieflysummarized above may be had by reference to the embodiments thereofwhich are illustrated in the appended drawings, which form a part ofthis specification. It is also to be noted, however, that the drawingsillustrate only various embodiments of the invention and are thereforenot to be considered limiting of the invention's scope as it may includeother effective embodiments as well.

FIG. 1 is a sectional view of a single slab support, illustrating aconcrete pier, housing, seal plate, and concrete slab.

FIG. 2 is a sectional view of the single slab support with the housingand the slab raised to a desired height.

DETAILED DESCRIPTION OF THE INVENTION

The present invention now will be described more fully hereinafter withreference to the accompanying drawings in which a preferred embodimentof the invention is shown. This invention may, however, be embodied inmany different forms and should not be construed as limited to theembodiment set forth herein; rather, this embodiment is provided so thatthis disclosure will be thorough and complete, and will fully convey thescope of the invention to those skilled in the art. Like numbers referto like elements throughout.

Referring to FIG. 1, a foundation slab 11 may be used to support a houseor other building. In this embodiment, the slab 11 is of concrete andinitially rests on a ground surface 12 and a support surface or pier 13.The foundation or slab 11 is typically supported by a plurality ofsupport surfaces or piers 13, but for simplification purposes, thesingle pier 13 will be discussed. In this embodiment, the pier 13 is ofconcrete and has a lifting assembly 15 embedded therein. The liftingassembly 15 consists of a liner 17 (optional), a housing 19, and a sealplate 21. In this embodiment, the housing 19 is a capped cylinder andthe seal plate 21 is circular in shape. The seal plate 21 rides withinthe interior of the cylinder 19 and is sealingly engaged with an innersurface 23 of the cylinder 19 by an O-ring 25, which rides in a slotaround the outer surface of the seal plate 21. A plurality of vent tubes27 are located in and extend through the seal plate 21 before extendingupward a select distance. A void 29 is initially present between theupper surface of the seal plate 21 and the closed end of the cylinder19. A plurality of apertures 31 are located in and extend through theclosed end of the cylinder 19. The apertures 31 are aligned with thevent tubes 27 and are adapted to accept the vent tubes 27 therein. Aninjection tube 33 is connected to a port 35 that is located in andextends through the closed end of the cylinder 19. The injection tube 33may be built as an integral part of the cylinder 19 or may be threadedthereon. In this embodiment, the injection tube 33 is formed as anintegral part of the cylinder 19.

The hole for the pier 13 is dug with a diameter such that the liftingassembly 15 is fully encased within the concrete. Once the hole is dug,the pier 13 is formed by pouring concrete into the hole. The liftingassembly 15 is then inserted into the concrete and pushed downward untilthe top surface of the cylinder 19 is substantially flush with theground surface 12. As previously discussed, the liner 17 surrounding thecylinder 19 may be simultaneously inserted into the pier 13.Alternatively, the outer surface of cylinder 19 may be coated with alubricant or form releaser. The inner surface 23 of the cylinder 19 iscoated with a lubricant or form releaser to prevent the concrete of thepier 13 from bonding to the cylinder 19. As the lifting assembly 15 islowered into the concrete pier 13, the air trapped within the cylinder19 escapes through the vent tubes 27 and the apertures 31. Once theconcrete pier 13 has solidified, the seal plate 21 will be securelyencased within the pier 13.

In this embodiment, a hollow pipe or support sleeve 39 has a diameterthat is less than the diameter of the cylinder 19. In an alternateembodiment, various reinforcing members may be connected to and extendoutwardly from the outer peripheries of the support sleeve 39 in variousshapes and configurations.

The support sleeve 39 is placed on top of the closed end of cylinder 19such that it surrounds the port 35 and the injection tube 33 (ifattached). The diameter of the support sleeve 39 is such that theapertures 31 in the seal plate 21 are positioned radially outward fromthe port 35 a greater distance than the walls of the support sleeve 39.The concrete may be kept from bonding to the concrete pier 13 and theliner 17 by a bond breaker layer (not shown) which is optional.

Referring to FIG. 2, after the slab 11 and the pier 13 have hardened,the injection tube 33, if not already connected to the port 35, isconnected to the cylinder 19. After the injection tube 33 is connectedto the port 35, a pumping device 41 is then connected to the injectiontube 33 by a connecting link 43. In this embodiment, the pumping device41 is a concrete pump. Concrete or grout is then pumped by the concretepump 41 into the link 43, through the injection tube 33, the port 35,and into the void 29 (FIG. 1) between the closed end of cylinder 19 andthe seal plate 21. As grout or concrete fills the space between thecylinder 19 and the seal plate 21, the cylinder 19 acts as a piston asthe concrete forces the cylinder 19 upwards relative to the groundsurface 12. The O-ring 25 maintains sealing contact between the sealplate 21 and the inner surface 23 of the cylinder 19. The bottom surfaceof the concrete slab 11 abuts against the apertures 31, therebypreventing the concrete or grout from exiting the cylinder 19 throughthe aperture 31. The concrete or grout is pumped into the cylinder 19until the foundation slab 11 is lifted above the ground to the desiredheight. Once the slab 11 has reached its desired height, the injectiontube 33 may be crimped or sealed and the grout or concrete within thecylinder 19 is permitted to harden and set up. The connecting link 43and the concrete pump 41 may be disconnected and removed. Once theconcrete or grout has set up, the new positions of the cylinder 19 andthe slab 11 are securely fixed at the desired heights.

The invention has significant advantages. The invention provides amethod and apparatus that allows a foundation to be poured on top ofsoil and subsequently raised to a desired height to eliminate potentialproblems caused by soil movement and/or problematic soils.

In the drawings and specification, there have been disclosed a typicalpreferred embodiment of the invention, and although specific terms areemployed, the terms are used in a descriptive sense only and not forpurposes of limitation. The invention has been described in considerabledetail with specific reference to these illustrated embodiments. It willbe apparent, however, that various modifications and changes can be madewithin the spirit and scope of the invention as described in theforegoing specification and as set forth in the following claims

1. A system for forming a movable slab foundation, the systemcomprising: a slab foundation; at least one support pier; at least onehousing positioned within the at least one support pier, the at leastone housing having a closed upper end and an open lower end; a sealplate positioned within and surrounded by the at least one housing, theouter peripheries of the seal plate sealingly engaging the innersurfaces of the at least one housing, the at least one housing beingupwardly moveable within the support pier relative to the seal plate; acavity defined by the space between the upper surface of the seal plateand the upper end of the at least one housing; a port located in andextending through the closed upper end of the at least one housing andinto the cavity; and at least one support sleeve, the at least onesupport sleeve being encased within the slab foundation, the bottomsurface of the at least one support sleeve abuttingly contacting theupper end of the at least one housing.
 2. The system of claim 1,wherein: the at least one housing is cylindrical in shape; and the sealplate is circular in shape.
 3. The system of claim 1, furthercomprising: an O-ring positioned between the outer peripheries of theseal plate and the inner surfaces of the at least one housing.
 4. Thesystem of claim 1, further comprising: an injection tube connected tothe port and extending upwardly through the interior of the supportsleeve; and a pumping device connected to the injection tube for pumpinga support media into the cavity to thereby expand the cavity and movethe housing, the support sleeve, and the slab foundation upwardsrelative to the seal plate.
 5. The system of claim 1, furthercomprising: a plurality of apertures located in and extending throughthe closed upper end of the housing; and a plurality of vent tubesconnected to and extending upwardly from the seal plate, the pluralityof vent tubes being aligned with and extending through at least aportion of the plurality of apertures.
 6. The system of claim 1, furthercomprising: a liner surrounding and positioned in abutting contact withthe outer peripheries of the housing, the liner fixably secured withinthe support pier.
 7. A system for faulting a movable slab foundation,the system comprising: a slab foundation; at least one support pier; atleast one housing positioned within the at least one support pier, theat least one housing having a closed upper end and an open lower end; aseal plate positioned within and surrounded by the at least one housing,the outer peripheries of the seal plate sealingly engaging the innersurfaces of the at least one housing, the at least one housing beingupwardly moveable within the support pier relative to the seal plate; acavity defined by the space between the upper surface of the seal plateand the upper end of the at least one housing; a port located in andextending through the closed upper end of the at least one housing andinto the cavity; at least one support sleeve, the at least one supportsleeve being encased within the slab foundation, the bottom surface ofthe at least one support sleeve abuttingly contacting the closed upperend of the at least one housing; and a pumping device connected to theport for pumping a support media into the cavity to thereby expand thecavity and move the housing, the support sleeve, and the slab foundationupwards relative to the seal plate.
 8. The system of claim 7, wherein:the at least one housing is cylindrical in shape; and the seal plate iscircular in shape.
 9. The system of claim 7, further comprising: anO-ring positioned between the outer peripheries of the seal plate andthe inner surfaces of the housing.
 10. The system of claim 9, furthercomprising: a plurality of apertures located in and extending throughthe closed upper end of the housing; and a plurality of vent tubesconnected to and extending upwardly from the seal plate, the pluralityof vent tubes being aligned with and extending through at least aportion of the plurality of apertures.
 11. The system of claim 10,further comprising: a liner surrounding and positioned in abuttingcontact with the outer peripheries of the housing, the liner fixablysecured within the support pier.
 12. The system of claim 7, furthercomprising: an injection tube connected to and extending between theport and the pumping device, the injection tube extending upwardlythrough the interior of the support sleeve.
 13. A method for forming amovable slab foundation, the method comprising: (a) providing a housingwith a closed upper end and an open lower end, a seal plate positionedwithin and surrounded by the housing, the outer peripheries of the sealplate being sealingly engaged with the inner surfaces of the housing, acavity defined by the space between the upper end of the housing and theupper surface of the seal plate, a port located in and extending throughthe closed upper end of the housing and into the cavity; (b) placing asupport pier below an intended slab foundation area; (c) treating theinner and outer surfaces of the housing with a form releaser; (d)positioning the housing and the seal plate within the support pier; (e)placing a support sleeve in abutting contact with the closed upper endof the housing; (f) forming a slab foundation such that it encases thesupport sleeve; and (g) pumping a support media through the port andinto the cavity, thereby expanding the cavity and simultaneously liftingthe housing and the support sleeve to move the slab foundation upwardrelative to the seal plate to a desired height.
 14. The method of claim13, wherein step (a) further comprises: providing a plurality ofapertures located in and extending through the closed upper end of thehousing, and a plurality of vent tubes located in and extending upwardlyfrom the seal plate, the vent tubes being aligned with the plurality ofapertures; and wherein step (d) further comprises: lowering the housingand the seal plate into the support pier; and venting any air trapped inthe housing through the vent tubes and the apertures.
 15. The method ofclaim 13, wherein the support pier is of concrete; and Wherein themethod further comprises between step (d) and step (e), allowing theconcrete support pier to set up, thereby encasing the seal plate in thesupport pier.
 16. The method of claim 13, further comprising after step(g): allowing the support media to set up, thereby securing the positionof the housing, the support sleeve, and the slab foundation relative tothe seal plate.
 17. The method of claim 13, further comprising afterstep (g): sealing the port in the closed upper end of the housing,thereby securing the position of the housing, the support sleeve, andthe slab foundation relative to the seal plate.
 18. The method of claim13, wherein step (a) further comprises: providing a liner surroundingand in abutting contact with the outer peripheries of the housing; andwherein step (d) further comprises: positioning the liner within thesupport pier.
 19. The method of claim 13, wherein step (g) furthercomprises: extending an injection tube through the interior of thesupport sleeve and connecting the injection tube between the port and apumping device.